关键词: 钛系催化剂, 聚酯, 色值, 性能, 固相缩聚

Abstract: To address issues of yellowish color and inefficient viscosity increment of slice prepared by traditional titanium catalyst, a new-type titanium-based catalyst was prepared. A polyester slice with good color and low by-product content was successfully prepared based on the titanium-based catalyst. The slice can also be further used to prepare high-viscosity slices for industrial yarns through solid-phase polycondensation. Through polymerization of the self-prepared new titanium catalyst, a polyester slice with a viscosity of about 0.65 dL/g at a lower dosage (2.5×10^-5)was obtained. Its properties were studied using Ubbelohde viscometer, volumetric titration, DSC thermal analysis, etc. The results indicated that the polyester prepared by this means was good in color, with b value of as low as 1.17, much lower than that prepared by the existing titanium catalyst (b value is 5.55). The carboxyl terminal concentration of the polyester was 16 mol/t, and the mass fraction of oligomer was about 2.0%. In addition, after solid-phase polycondensation at 230 ℃ for 8 h, its intrinsic viscosity reached 1.10 dL/g, with high efficiency in viscosity increment. This study can provide a useful reference for the large-scale application of titanium-based catalysts in polyesters.

Key words: polyester, titanium catalyst, color value, property, solid phase polycondensation